Dragon Flight by Jessica Day George
With the Dragon Wars over, Creel finds herself bored with life as a seamstress. Then word comes that a bordering country has been breeding dragons in preparation for an invasion. Never one to sit around, Creel throws herself headlong into an adventure that will reunite her with her dragon friend Shardas, pit her against a vicious new enemy and perhaps rekindle a friendship with Prince Luka that seems to have gone cold. This is a sequel to Dragon Slippers.